1. Field of the Invention
The present invention relates to an electrochemical cell such as an electric double layer capacitor and an ion capacitor.
2. Description of the Related Art
An electric double layer capacitor that is an electricity storage device includes a pair of polarizable electrodes, a separator interposed between the pair of polarizable electrodes, and an electrolytic solution with which the pair of polarizable electrodes and the separator are impregnated, in a housing container sealed with a lid body and a container main body. In various small-sized electronic devices, such as mobile phones, PDAs, and handheld game consoles, such an electric double layer capacitor is utilized as a backup power source for memories, a backup power source for clock functions, and the like. As this kind of electric double layer capacitor, an electric double layer capacitor of a button type having a disc shape is widely used. In addition, an electric double layer capacitor of a chip type having a rectangular shape has also been proposed (see, for example, Patent Documents 1 and 2).    Patent Document 1: JP-A-2001-216952    Patent Document 2: JP-A-2012-64922